Performance investigation on a linear Fresnel lens solar collector using cavity receiver

• A linear Fresnel lens collector with four types of cavity receivers was proposed and studied.
• Heat transfer analysis of four types of cavity receiver were conducted.
• Ray tracing method was used to predict the optical performance of the collector.
• Performance of the collectors were evaluated numerically and experimentally.

The optical and thermal performance of a linear Fresnel lens solar collector using different types of cavity receiver is presented in this paper. The optical properties of the proposed Fresnel lens solar collector was predicted by employing Monte Carlo ray trace method and thereby radiation distribution as well as the impact of incidence angle on optical performance was obtained. Triangular cavity receiver was found to have highest optical efficiency of 81.2%. Thermal performance was investigated by employing both numerical and experimental method. 2D mathematical model was developed considering conductive, convective and radiative heat losses. The CFD model was then validated by comparing simulation results with experimental results. For Fresnel lens solar collector with triangular cavity receiver, the thermal efficiency was found to be around 30% at 120 °C. The analysis confirms that the Fresnel lens solar collector with triangular cavity receiver boasts best performance in terms of both optical and thermal characteristics.